1830, On the Art of Rising in Prose The New Monthly Magazine and Literary Journal, part 2, v. 29, Henry Colburn and Co., page: 162:

“The fine old fellow,” as a Northern contemporary of ours patronizingly calls him, certainly rolled out his sesquipedalians with a majesty previously unknown, and gave a fine organ-like swell to his full-blow periods;

1927, John S. Farmer, William Ernest Henley, A Dictionary of Slang and Colloquial English: Abridged from the Seven-volume Work, Entitled "Slang and Its Analogues", Taylor & Francis, page: 164:

Fleet-streetese, the so-called English written to sell by the Fleet-streeter (q.v.), or baser sort of journalist: a mixture of sesquipedalians and slang, of phrases worn threadbare and phrases sprung from the kennel;

Our dinner guest was so sesquipedalian that no one could understand what he said.

2014 October 30, Ben Brantley, “When the head leads the heart: 'The Real Thing,' With Ewan McGregor and Maggie Gyllenhaal, opens on Broadway [print version: When the witty head is far ahead of the heart: Maggie Gyllenhaal and Ewan McGregor star in revival of 'Real Thing', International New York Times, 4 November 2014, p. 9]”, in The New York Times[1]:

[I]ts main character, Henry (Mr. [Ewan] McGregor), is a successful, intellectual dramatist who seems quite capable of churning out fizzy, challenging works about brilliant but ambivalent revolutionaries, philosophers, etc. […] But this cleverer-than-thou creature gets his comeuppance in "The Real Thing," showing that a very human heart – just like those possessed by the less sesquipedalian – beats beneath his fancy words.